Intramedullary changes of the spinal cord in cervical spondylotic myelopathy.

Abstract

This study retrospectively reviewed magnetic resonance imaging and delayed computed tomography after myelography of cervical spondylotic myelopathy patients who needed surgical treatment. The purpose of this study is to clarify the meaning of high magnetic resonance intensity areas in cervical spondylotic myelopathy patients. There is no conclusion whether the high magnetic resonance signal intensity areas can be a predictor for surgical results or not. Thirty-one patients with cervical spondylotic myelopathy were examined with magnetic resonance imaging before surgery and delayed computed tomography after surgery. The presence or absence of high intensity areas in the spinal cord was compared with clinical symptoms and surgical outcomes. Twenty-three (74%) of 31 patients showed high intensity areas in the spinal cord on the T2-weighted image. Among these 23 patients, 18 revealed bilateral intramedullary "snake eyes" enhancement in delayed computed tomography. The presence of high intensity areas did not correlate with the surgical outcomes. Patients with multisegmental (linear) high intensity areas frequently manifested muscle atrophy in upper extremities. High intensity areas on T2-weighted magnetic resonance imaging were not correlated with the severity of myelopathy or surgical outcomes evaluated by the Japanese Orthopaedic Association score. Magnetic resonance imaging or delayed computed tomography in this study could not rule out the presence of white matter changes, including axonal loss or demyelination. Multisegmental (linear) high intensity areas on T2-weighted magnetic resonance imaging were associated with clinical evidence of extensive anterior horn cell and radiographic evidence of gray matter cavitation.